Yes I agree with the playpen. Also make sure you have a very good, baby safe insect repellent and sunscrean is also important. Make sure you check him every night for ticks, especially in skin folds and diaper areas, even if you don't think he could have been in an area where he could get one.
Lots and lots of baby wipes - they are good for cleaning hands and face as well as diaper area. And bring about twice as many diapers as you think you'll need. There's not much worse than running out halfway through camping, especially if you don't have a town close by to run and get some.
The youngest we took a child camping was 14 months, so he was walking. We took a kiddie leash - it has a cute harness that goes around his chest and a short leash attached. I know lots of people object to leashes, but it was much better than the chance of him wandering off (he did that a lot) where there are lots of places to get lost and very few people to come across him. You may want to consider one if he starts crawling at all.
And don't forget the camera! There are sure to be some cute things you want to take pictures of!